The reel continues with Barkley spinning and juking through tackles, throwing stiff-arms and shoulders to grind out a few more yards. In concludes as it began, with Barkley going airborne over incoming defenders aiming low at his massive calves.

Barkley's mom isn't a fan of the technique that catapulted her son into the college football spotlight on just his seventh career carry.

''She says it's risky,'' Barkley said. ''Personally, I don't like it either. But you just get so caught up in the emotions of the game and the adrenaline you have, your heart's pumping and you feel like you can do anything. It just happens.''

Following his 1,076-rushing-yard season, where his big-play ability was often the saving grace for Penn State's 105th-ranked offense, Barkley is less concerned midway through spring practice with making big plays in the moment. He's realized, to be the focal point of coordinator Joe Moorhead's offense, he'll have to develop from the all-or-nothing playmaker he was as a freshman.

Barkley's explosive-play stats speak volumes - his 15 runs of 20-plus yards were 11th in the country despite playing two less games than most of the players ahead of him. But he's focusing on his 44 carries that resulted in no gains or lost yardage.

He wants to improve in the non-flashy aspects of the position. That's staying on the field in passing situations, whether to add another dimension as a receiver out of the backfield, sell himself as a decoy or protect his quarterback from pressure.

''It's your natural instinct to try and make a guy miss, try to be special,'' Barkley said. ''I tried to do too much. I had some drops last year, I messed up in pass protection a lot. I just want to be like the quarterback. I want to be able to look at a defense and see what blitz is coming or when I run the ball, alright, this is going to open up here and just be more of a student of the game.''

A self-described fan of ''old-school running backs,'' Barkley has added hours of film study to his regimen. When he's not watching Walter Payton, Barry Sanders and Eric Dickerson, Barkley pulls up video of backs that finished ahead of him on last season's explosive-play list.

Barkley admires Florida State's Dalvin Cook's speed ''in a phone booth'' and is consumed with how LSU's Leonard Fournette steps up to eliminate blitzers. The Penn State back wants to execute crisp receiving routes like Stanford's Christian McCaffrey.

The Coplay, Pennsylvania native's coaches and teammates know Barkley has the physical tools.

His 4.3 forty-yard-dash time tops the leaderboard inside the team's weight room and videos of him cleaning and squatting 390 and 495 pounds, respectively, have made their rounds. The girth of Barkley's lower legs once prompted a teammate to insist he'd never lend Barkley his socks.

''You look at his size and strength and speed numbers, they are as good as anywhere in the country, college or I would even say the NFL,'' Penn State coach James Franklin said. ''How can we make sure that translates onto the field with him, with the scheme, with the improvements that we are making on the offensive line with their experience and their strength and their size and the depth that we have there?''

Barkley believes isolation is the key. It's how Moorhead's offense is designed and why Barkley's eyebrows quickly climb his forehead when asked to describe it.

''One word to explain it, I'll say fast,'' Barkley said. ''I really like it and I believe in it because it gets your playmakers in one-on-one situations.''

It's why the team's offensive linemen have made bigger commitments to nutrition this offseason. They want to be able to maintain the pace they know their star back can set. They know if they do so, Penn State's offense won't return the lackluster results it has the last two years.

''Saquon's a freak. Everyone knows that,'' tackle Andrew Nelson said. ''As an offensive line it gives you that, if I just hold this block for one more second, Saquon will spit this thing. He's a playmaker.''